Answer this !
what is the y-intercept of the function represented by the tables of values below ?
a. 9
b. 6
c. 3
d. 12

Y = mx + b

m is the slope

we can find the y-intercept by figuring out what b is, because...

if we pretend the slope of the line is 0 and put 0 in m...

y = 0x + b
y = b

and only one point is going to go through a point on the y-line - the y-intercept

all we have to do is find b

now, we can just use any points on this imaginary line using the table of values to put in the y and x portion of the equation

let's use (-2, 15) for example
y = mx + b
15 = m(-2) + b
or
15 = -2m +b

but we still need to find the slope (m) in order to solve the equation and get b (y-intercept)

so, we can take this equation to find what the slope
m = (y2 - y1) / (x2 - x1)
we need two points to solve this equation. let's use (1, 6) and (2, 3)

in this equation, y2 is the y of (2, 3), the second point, and y1 is the y of (1, 6), the first point.

y2 = 3
y1 = 6

similarly, x2 is the x of (2, 3), the second point, and x1 is the x of (1, 6), the first point.

x2 = 2
x1 = 1

let's put it in the equation

m = (y2 - y1) / (x2 - x1)
m = (3 - 6) / (2 - 1)
m = -3 / 1
m = -3

the slope, m, is -3

let's put it in the first equation, along with the random point we selected earlier (-2, 15).

y = mx + b
15 = -2m +b
15 = -2(-3) + b
15 = 6 + b
15 - 6 = 6 - 6 + b
9 = b
b = 9

the y-intercept is 9

so, A. :))